Indole → 4,5-dimethyl-1H-indole-3-carboxylic acid

Participants

Role	Name	HCID	Charge
Reactant	Indole	HCID 798	—
Reactant	Potassium Carbonate	HCID 11430	—
Reactant	1,4-Dioxane	HCID 31275	—
Reactant	Methylboronic Acid	HCID 139377	—
Catalyst	Bis(cyclopenta-1,4-dien-1-yl(diphenyl)phosphane);dichloropalladium;iron(2+)	HCID 178418228	—
Product	4,5-dimethyl-1H-indole-3-carboxylic acid	HCID 57057416	91.8%

Reaction Conditions

Temperature	90 °C

Reaction Steps

A mixture of bromide 1 (1.0 g, 4.78 mmol), methyl boronic acid (860 mg, 14.3 mmol), Pd(dppf)2Cl2 (194 mg, 0.239 mmol), and K2CO3 (1.32 g, 9.56 mmol) in dioxane (20 mL) was degassed and stirred at 90° C. for 5 h under nitrogen. The reaction mixture was concentrated, and the residue was purified by silica gel chromatography (EtOAc/petroleum ether=1/4) to give the desired product (636 mg, 4.39 mmol, 91.8%) as a white solid.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US09434724B2
Source dataset	uspto-grants-2016_09
ORD ID	ord-bc86db76d4f148378e7240faa3b5a944
Source note	uspto-grants-2016_09